Latest Research Findings

Dehydroepiandrosterone Sulfate Levels Are Associated with More Favorable Cognitive Function in Women

Susan R. Davis, Sonal M. Shah, Dean P. McKenzie, Jayashri Kulkarni, Sonia L. Davison,  & Robin J. Bell

Women's Health Program (S.R.D., S.M.S., S.L.D., R.J.B.), Department of Medicine, Monash Medical School, Alfred Hospital, Prahran, Victoria 3181, Australia; and School of Psychology, Psychiatry and Psychological Medicine (S.M.S., J.K.) and Department of Epidemiology and Preventive Medicine (D.P.M.), Monash University, Prahran, Victoria 3181, Australia

Context:  It has been proposed that dehydroepiandrosterone and dehydroepiandrosterone sulfate (DHEAS) exert neuroprotective effects in the brain, yet evidence of associations between the endogenous levels of these steroids and measures of cognitive function is lacking.

Objective: The objective of the study was to investigate whether circulating levels of DHEAS independently contribute to aspects of cognitive function in women in the community.

Design: This was a community-based, cross-sectional study.

Setting and Participants: Two hundred ninety-five women, aged 21-77 yr, were recruited from a community-based data set and participated between September 2003 and December 2004. Women were excluded if they reported any health condition that might potentially adversely affect cognitive function.

Main Outcome Measures: The individual scores of a comprehensive battery of tests of cognitive function and the serum level of DHEAS (square root transformed) were measured.

Results: In the multiple linear regression analysis, the DHEAS term made a significant independent positive contribution to the Controlled Oral Word Association Test score, a measure of executive function. In addition, women with a DHEAS level in the highest tertile who also had more than 12yr of education performed betteronboth Digit Span Forward and Digit Span Backward tests, which are tests of simple concentration and working memory, respectively.

Conclusions: Higher endogenous DHEAS levels are independently and favorably associated withexecutive function, concentration, and working memory.

 (Published in full in J Clin Endocrinol Metab 93: 801-808, 2008)

Effects of tibolone and raloxifene on bone mineral density in osteopenic postmenopausal women.

1PD Delmas, 2SR Davis, 3J Hensen, 4S Adami, 5 S van Os, 5EA Nijland

(1.) INSERM Research Unit 831 and Université de Lyon, Lyon, France; (2.) Monash Medical School, Prahran, Australia; (3.) University of Erlangen, Erlangen, Germany; (4.) University of Verona, Valeggio sul Mincio VR, Italy; (5) Global Clinical Development, NV Organon, Oss, The Netherlands.

A randomized trial was conducted in osteopenic postmenopausal women to compare the efficacy of tibolone versus raloxifene on BMD of the lumbar spine and hip. Tibolone increased lumbar spine and total hip BMD to a statistically significantly greater extent than raloxifene after two years of treatment.

INTRODUCTION: Both tibolone, a selective tissue estrogenic activity regulator (STEAR), and raloxifene, a selective estrogen receptor modulator (SERM), are known to prevent postmenopausal bone loss. However, no head-to-head studies to compare the efficacy on bone have been performed.

METHODS: A double-blind, randomized trial was conducted in osteopenic postmenopausal women aged 60-79 years to compare the effects of tibolone 1.25 mg/day to raloxifene 60 mg/day on bone mineral density (BMD). Serum osteocalcin and serum type I collagen C-telopeptides were measured as biochemical markers of bone metabolism. RESULTS: Three hundred and eight subjects were allocated to treatment. Both treatments significantly increased lumbar spine BMD, however the increase was significantly larger after tibolone treatment than after raloxifene treatment (at year 1: 2.2% versus 1.2%, p < 0.01 and at year 2: 3.8% versus 2.1%, p < 0.001). After 2 years of treatment, the increase in total hip BMD in the tibolone group was significantly larger than in the raloxifene group (p < 0.05). Both treatments significantly reduced type I collagen C-telopeptides and osteocalcin levels when compared to baseline.

CONCLUSIONS: Tibolone 1.25 mg/day for 2 years prevents postmenopausal bone loss in older women and results in a larger increase of BMD both at the lumbar spine and hip than raloxifene.

(Published in Osteoporosis International: E publication Feb 2008 ahead of print.)

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